20328987 has 16 divisors (see below), whose sum is σ = 32325120. Its totient is φ = 11111232.

The previous prime is 20328983. The next prime is 20329003. The reversal of 20328987 is 78982302.

It is not a de Polignac number, because 20328987 - 2² = 20328983 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20328983) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20562 + ... + 21527.

It is an arithmetic number, because the mean of its divisors is an integer number (2020320).

Almost surely, 2^20328987 is an apocalyptic number.

20328987 is a deficient number, since it is larger than the sum of its proper divisors (11996133).

20328987 is a wasteful number, since it uses less digits than its factorization.

20328987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42122.

The product of its (nonzero) digits is 48384, while the sum is 39.

The square root of 20328987 is about 4508.7677917586. The cubic root of 20328987 is about 272.9220214969.

The spelling of 20328987 in words is "twenty million, three hundred twenty-eight thousand, nine hundred eighty-seven".